The absolute “one” is also of two kinds: the theoretical and the actual.
The theoretical “one” is the numerical “one,” the foundation and beginning of all numbering. It is the sign and symbol of a beginning before which there is no beginning, for every absolute beginning is called “one,” as it says: “There was evening there was morning, one day (Bereishit 1:5). Instead of saying “the first day,” the verse says “one day,” because “one” is the term for any beginning before which there is no beginning. When doubled, it is called “second”; when tripled “third,” and so on, until ten, when it returns to the number one; it then goes onto one hundred, a thousand, and so on, without end. The definition of number is therefore the sum of many ones.
The second kind of absolute “one” exists actually. It is that which cannot be increased, changed, of transformed; nor can it be described by any one of the physical attributes. It is not subject to creation and destruction, or to any ending. It neither changes position nor moves. It is not like anything, nor is anything like it, nor is it associated with anything.